This paper is devoted to study the symmetries of the energymomentum tensor for the static spacetimes with maximal symmetric transverse spaces. We solve matter collineation equations for the four main cases by taking one, two, three and four non-zero components of the vector ξ. For one component non-zero, we obtain only one matter collineation for the non-degenerate case and for two components n...

We prove a weighted norm inequality for the maximal Bochner-Riesz operator and the associated square-function. This yields new L(R) bounds on classes of radial Fourier multipliers for p ≥ 2 + 4/d with d ≥ 2, as well as space-time regularity results for the wave and Schrödinger equations.

Mining of frequent traversal paths in web logs is an application of sequence mining and useful with many applications that include web recommendation, caching, pre-fetching etc. Most of the existing algorithms follow a bottom-up approach to mine sequence patterns in a database. In this paper, a fast top-down algorithm is presented to discover maximal traversal paths which are contiguous sequenc...

We show that the Hardy-Littlewood maximal operator and a class of Calderón-Zygmund singular integrals satisfy the strong type modular inequality in variable L spaces if and only if the variable exponent p(x) ∼ const.

We present a framework that yields a variety of weighted and vector-valued estimates for maximally modulated Calderón-Zygmund singular (and maximal singular) integrals from a single a priori weak type unweighted estimate for the maximal modulations of such operators. We discuss two approaches, one based on the good-λ method of Coifman and Fefferman [CF] and an alternative method employing the s...

We study information as an incentive device in a dynamic moral hazard framework. An agent works on a task of uncertain difficulty, modeled as the duration of required effort. The principal knows the task difficulty and can provide information over time with the goal of inducing maximal effort. The optimal mechanism features moving goalposts: an initial disclosure makes the agent sufficiently op...

Let R be a two-dimensional regular local ring with maximal ideal m, and let ℘ be a simple complete m-primary ideal which is residually rational. Let R0 := R $ R1 $ · · · $ Rr be the quadratic sequence associated to ℘, let Γ℘ be the value-semigroup associated to ℘, and let (ej(℘))0≤j≤r be the multiplicity sequence of ℘. We associate to ℘ a sequence (γi(℘))0≤i≤g of natural integers which we call ...

In this paper, we explore a general method to derive H ! L boundedness from H ! H boundedness of linear operators, an idea originated in the work of Han and Lu in dealing with the multiparameter flag singular integrals ([19]). These linear operators include many singular integral operators in one parameter and multiparameter settings. In this paper, we will illustrate further that this method w...

This is the third part of a series of four articles on weighted norm inequalities, off-diagonal estimates and elliptic operators. For L in some class of elliptic operators, we study weighted norm L inequalities for singular “non-integral” operators arising from L ; those are the operators φ(L) for bounded holomorphic functions φ, the Riesz transforms ∇L−1/2 (or (−∆)1/2L−1/2) and its inverse L1/...

We study the convergence of maximal monotone operators with the help of representations by convex functions. In particular, we prove the convergence of a sequence of sums of maximal monotone operators under a general qualification condition of the Attouch–Brezis type.